<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
	</head>
	<body>
		<button>后退的</button>
		
		
		
		
		<script type="text/javascript">
			
			var btn = document.getElementsByTagName("button");
			
			
			btn[0].onclick=function(){
				history.go(-1)
			}
			
			
		</script>
	</body>
</html>
